示例代码：
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>jQuery扩展的两种方法</title>
<style>
div{
cursor: pointer;
}
</style>
</head>
<body>
<div id="i1">看帅哥吧</div>
<div id="i2">看美女吧</div>
<script src="jquery-1.12.4.js"></script>
<script>
$.extend({
"chong" :function () {
return "帅哥";
}
});
$.fn.extend({
"dan":function () {
return "美女";
}
});
$('#i1').click(function () {
var boy = $.chong();
alert(boy);
});
$('#i2').click(function () {
var girl = $('#i2').dan();
alert(girl);
});
</script>
</body>
</html>